The gas , which is sulphur - free , contains 89 - 99 % methane, up to 6 % ethane, and 3 % propane.

天然气不含硫, 含甲烷88-99%, 乙烷6%和丙烷3%.

辞典例句

N - octylic acid - N - ( quinazolin - 4 - ketone ) ester is a sulphur - free and phosphorus - free additive.

正辛酸 -N- ( 喹唑啉 -4- 酮 ) 甲酯是一种无硫、无磷的添加剂.

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